Blade edge deformation tester



Feb. 23, 1960 E. J. cAssELMAN BLADE EDGE DEFORMATION TESTER 3 Sheets-Sheet l Filed April lO, 1957 INVENTOR. wma raam Feb. 23, E960 E. J. CASSELMAN 2,92533@ BLADE EDGE DEFORMATION TESTER Filed April lo, 1957 s sheets-sheet 2 VII/ll /l IN VEN TOR.

Feb. 23, i960 E, J. cAssL-:LMAN

BLADE EDGE EEEORMA'TION TESTER 3 Sheets-Sheet 5 Filed April l0, 1957 lNVNToR.

United StatesPatent C 2,925,730 BLADE EDGE DEFORMATIN TESTER Elbridge J. Casselman, Harrisonburg, Va., assignor to American Safety Razor Corporation, New York, N.Y.,

a corporation of Virginia Application April 10, 1957, Serial No. 651,937

7 Claims. (Cl. 73-104) The present invention relates to a mechanism for simulating the deformation of a cutting edge during use and more particularly to a mechanism for dulling a blade edge to the same extent as the blade is dulled during normal use.

Such mechanisms are used in connection with blade edge testing devices wherein the sharpness of a cutting edge is first tested on a blade testing mechanism, the blade is then dulled by a mechanism which simulates the actual deformation taking place in the blade edge during normal use, and thereafter the blade is again tested o n theedge testing mechanism to measure the difference in the sharpness of the blade edge before and after the dulling operation. This will give an effective indication of the degree to which the blade edge will be deformed in normal use.

l One object of the present invention is to provide a blade dulling mechanism which will dull blades uniformly.

lAnother object of the present invention is to provide a dulling mechanism which will dull the blades at a predetermined specific rate.

'A further object of the present invention is to pro vde al blade dulling mechanism which will stop automatically after a predetermined number of dulling operations. l

A still further object of the present invention is to provide a blade dulling mechanism which is'simple to operate and inexpensive to manufacture.

Other and further objects of the present invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims, and various advantages not referred to herein will'occur to one skilled in the art upon employment of the invention in practice.

A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawings, forming a part of the specification, wherein:

" Fig. 1 is a top plan view showing the blade dulling mechanism;

r" Fig. 2 is a side elevation thereof;

"Fig y3 is Aan enlarged ltop view of the blade holding clip; l

' f- Fig. 4 is a side elevation thereof;

- Fig.vv 5 is an enlarged side view of the disc brake assembly; and

Fig. 46 is a diagrammatic view showing the electric circuit for the blade dulling mechanism.

For convenience 'of description, the application has been directed to amechanism for dulling a razor blade, but it will be understood that it is within the scope of the present invention to apply to all typesof blades and cutting edges.

Referring more particularly to Figs. land 2, the blade dulling mechanism comprises 'a'frame 1 having a turntable 2 rotatably mounted thereon by means of shaft 3. `A' vclriv'e motor mounted on frame 1 to rotate the VICC shaft 3 and turntable 2 through the intermediation of gears 5 and 6.

Mounted on turntable 2 are a plurality of razor blades 7 which are held thereon by means of clips 8. In order to properly position the blades 7 on the turntable 2, a plurality of pairs of pins 9 and 10 are provided on the turntable 2 (Figs. 3 and 4). The pin 9 is adapted to enter the end notch in the blade and the pin 10 is adapted to engage a longitudinal edge of the blade to so locate the blade 7 that a portion of the shaving edge 7A of the blade 7 extends beyond the edge of the turntable 2.

The blade dulling medium is comprised of a strip of material or tape 11 which is unwound from the roll 12. The tape 11 passes over a frame 13 which is angled so that it will lie in the path of the rotating blade edges 7A. The frame 13 has a slit 14 (Fig. 2) therein to permit the blades to pass therethrough. The tape 11 is preferable made of paper and is rolled onto the roll 15, which is driven by the drive motor 4.

As the tape 11 moves over the inclined frame 13, the blades 7 are rotated so that they will cut through the tape 11 as they pass through slit 14 in frame 13. Each time a blade cuts the tape 11, its cutting edge will become duller. After a predetermined number of cuts is made, the machine is stopped and the blades are tested for sharpness.

In orderto automatically stop the machine after a predetermined number of blade cuts, a friction brake 16 is mounted on the shaft2 (Figs. 2 and 5). The friction brake 16 is comprised of a lower brake discl 17 mounted to rotate with the shaft 3 and an upper brake disc 18 mounted loosely around the shaft 3. The upper brake disc 18 is provided with upstanding elements 19 which act as the armatures for solenoids 20. Springs S are interposed between the armatures 19 and the solenoids 20 so that the upper brake disc 18 is biased toward the lower brake disc 17. When the solenoids 20 are energized, the armatures 19 are pulled up-so as to separate the brake discs 17 and 18 and permit the shaft 3 and turntable 2 to rotate. When the blades 7 have made a predetermined number of cuts in the tape 11, the solenoids 20 are de-energized, the springs S located between the solenoids 20 and armatures 19 force the disc 18 down to frictionally engage the disc 17 and stop rotation of the shaft 3.

The means for de-energizing the solenoids 20 are more clearly shown in Fig. 6. A limit switch 21 (Fig. 2) is activated by each revolution of the shaft 3, which in turn activates the stepping relay 22 one step. The

last step of the relay 22 is connected to the solenoidsv 20 and the drive motor 4. When the last step is reached (in the embodiment shown in the drawings, there are ten steps shown to permit ten revolutions of the shaft 3 before stopping), the current to the motor 4 and the solenoids 20 is turned off, thereby stopping the motor 4 and de-energizing the solenoids 2.0. This permits the nal'24'throu'gh leads 25 and 26'in seriesl witlrsaidpu'shbrake discs 17 and 18 to frictionally engage each other to s top rotation of the shaft 3.

The operation of the device is as follows: The blade edges 7A are first tested for sharpness in any conventional or desired manner; for example, they may be tested by a sharpness testing machine utilizingl scanning beams. After the sharpness of vblades 7 are recorded, they are mounted on the turntable 2 by inserting them under the clips 8. To properly locate the blades 7, their end notches are fitted into pins 9 and one of the longitudinal edges is placed into engagement with the pins 10. This so locates the blade 7 that their cutting edges 7A protrude beyond the table 2. t

When the instantaneous starter push button 23 is momentarily closed, current is fed from a power termi-v button 23 'to the winding 27 of a starter switch 28 and then through a lead 29 to the other power terminal 30. Energization of said winding 27 closes the normally open contacts ,of the power switch and thereby feeds power through mains 31, 32 to the motor 4 to start rotation of the shaft 3. At the same time branch leads 33, 34 feed current to the solenoids 20 `forenergization thereof. To maintain the switch 28 vclosed after the push button 23 is released and returned to its normally 'open position, I utilize a hold circuit constituting a lead y35 running from the main 31 through a normally `closed relay switch 36 and a lead 37 lto the winding A27 for the starter switch 28. It now will be seen that depressing the push button 23 first closes the starter switch and then energizes the hold circuit for the `starter s witch so that releasing the push button permits the starter switch to remain closed so long as the relay switch 36 stays closed. Concurrently with actuation of the motor `through the mains 31, 32 the solenoids 20 are energized pulling the armatures against the action yof the springs S so as to release the brake 16 and thereby permit the shaft 3 and table 2 to rotate.

Themotor 4 also drives the tape roller- 15, which pulls the tape 11 over the inclined frame 13 so that the tape is pulled over the opening 14 in the frame 13. Since the tape 11 is in the path'of ythe revolving blades 7,- the blades 7 will cut the tape l11 aseach blade 7 passes through opening 14. Each time the blade cuts the tape 11, its cutting edge 7A is dulled.

The power terminals 24, 30 (common power terminals are used for the various parts of the circuit but are shown in separate pairs for convenience) are connected toopposite sides of an actuating rwinding 38 of the stepping relay 22 through leads 39, 40, 41. Thereby, each time the limit switch 21 which connects the leads'39, 40 is closed, the actuating winding`38 is momentarily energized. The energizationis suiiicient to pull the stepping contact arm 42 of the relay 22 from one'contact to the next. None ofthe contacts of the relayY except the first and last are connected incircuit. AHowever', the i'irst contact 43 is connected'by a `lead wire 44v lto the lead 40 so that as long as the limit switch 2,21 is closed, this occurring once each revolutionof the table 2, potential will be placed upon the lirst contact. Said first contact is connected vby a Vlead 45 to the contact arm 42 so that this arm likewise has potential placed thereupon for a short period once each revolution of the table. It now will be apparent that eachhtime the normally open contacts of the limit switch are closed, the contact arm 42 of the stepping switch will advance from one contact to thenext. Ultimately, after a predetermined number of steps (ten in the embodiment shown) the contact arm 42' will arrive at the last contact 46. This contact is connected by a lead 47 to the actuating winding 48 of a relay 49 including the relay switch 36. A lead 50 completes Vthe connection vfor the actuating winding 48 back to the lead`41. Thereby when in the due course of time the stepping Contact arm '42 reaches the last contact,46, theact'uating winding 48 will be energized to'render the'relay` 49 perative. r-This in turn opens the switch 3.6'and thereby opens Vthe holding circuit for the starter switch 2K8. 'Ihus, the motor will be stopped and concurrently therewith the solenoids 20 will be deenergized thereby permitting the'springs S to render the brake eiective to stop rotation of the shaft 3. The mechanism then will stand idle until the push button 23 is again'clo'sed. It also will be observed that the relay 49 has Va normally open switch 51, which by means of lead wires 52, V53 will, when the actuating coil 48 is energized, supply power t'oan auxiliary actuating winding 54 of the stepping relay, the other terminal of said winding being connected by a ylead line 55 to the lead line 41. Closure of the switch 51 supplies an additional pulse to the stepping relayto move the contacflm f4.2.rmthe last Contact 461. the it .mest

43. This prepares the circuit for a fresh cycle by locating the contact arm on the first step and by deenergizingl the actuating winding 48 so as to permit the switch 36 to be returned to normally closed position.

After completion of a cycle the blades 7 are removed from the table 2 and again tested in a testing machine to determine the extent of wear on the cutting edge. With such data, improved cutting edges can be easily devised.

It will be seen from the above that the present invention provides a blade dulling mechanism which will dull blades uniformly at a specific rate; which will stop the dulling operation automatically; and which is simple to operate and inexpensive to manufacture.

As various changes may be made in the form, construction, and arrangement of the facts herein without departing from the spirit and scope of the invention and without'sacrificirig any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in la limiting sense.

Having thus described myinvention, Iclaim:

l. In a mechanism for subjecting the cutting edgeof a plane razor blade to auniforrn dulling action, kmeans mounting theblade for travel in a closed path including a plane portion during thetraversal of which .the blade is bodily moved in its own plane withthe cutting edge thereof foremost, a source of supply of .a cuttable web, and means moving the web from said source through `a path of travel a portion of which partially intersects the path of travel of the cutting edge ofthe blade sothat said web will be repeatedly sliced -at vintervals by said cutting edge up torp'oints inwardlyifrom .an edge of theweb to dull said cutting edge.

2. A mechanism as set forth in .claim l wherein the angle between lthe plane portion of the path of travel of the blade and the intersected portion of the path of travel of the web is substantiallyless Athan 3. A mechanism as set forthvin claim 1 whereinthe cutting edge of lthe blade is at an angle,substantially other than 90 with respect. to the direction of movement of the blade in theplaneportionof its path of travelso that the `blade progressively `slices the web during its engagement therewith.

.4. A mechanism as set forth in claiml whereinV means is providedk to' stop movement .of the blade `after a pre,- determined number of circuits of the blade through its closedpath. 1

5. A mechanism asset Iforth in claim l wherein the means mounting; theabladc-fortravel constitutes a turntable, and means Asupporting a blade on the turntable with the planeV thereof `perpendicular, to the axis of rotation of the turntable.

6. A mechanismlas setforth in `claim 5 whereinthe means supporting the blade on the turntable constitutes a -pair of pins on the turntable oneofthe pins abutting an end edge of the blade and the other pinabutting the back edge ,of the blade, .and wherein a Vclip issecured to the turntable to hold the blade in place.

7. A mechanism as set forth in claim, 1 .wherein means also vis included to Support the web at the portion of the path of travel thereof which partially intersects the path of travel of the cuttingedge of the blade, said means including anopening in the support on theundersurface of the web so that the web is supported adjacent, b utnot at the portion thereof which is sliced by the cutting edge.

- References Cited virl-the iile` of this patent UNITEDVSTATES PArENTs 

